Problem: Umaima has dinner at a cafe and the cost of her meal is $\$40.00$. She would like to leave a $10\%$ tip. What is her total bill including tip?
The tip amount is equal to $10\% \times \$40.00$ To calculate a $10\%$ tip, move the decimal point in $\$40.00$ one place to the left. $10\%$ $\times \$40.00$ $\$4.00$ The cost of the meal plus the amount of the tip will equal the total bill amount. $\$40.00 + \$4.00 = $ $\$44.00$ The total cost of the bill is $\$44.00$.